Author Topic: Glow plug relay WTF (Read 2395 times)

rabbicamino · « **on:** October 18, 2008, 02:59:18 pm »

I am wrapping up my gas to diesel conversion on my 81 rabbit pickup and I just finished conneting the glow plug relay. The only connection I haven't connected is the temp sensor input. After hooking it all up (sans temp sensor) I tested the relay and when the ignition is switched on the relay stays on for like 45 seconds. I thought the relay is only supposed to run for 7 seconds or so! I have a MK1 diesel bentley manual, and the testing sequence for the relay involves disconnecting the temp sensor. Would the temp sensor's absence make the relay run for 8 times longer than usual! Help!

jtanguay · « **Reply #1 on:** October 18, 2008, 03:01:06 pm »

sounds like you have the slow glow relay... you need to purchase the faster relay. but i think you might even need different glow plugs if you ordered ones for a 1981 diesel.

rabbicamino · « **Reply #2 on:** October 18, 2008, 03:05:00 pm »

I ordered the fast glow relay! I guess the could have mis-picked the part. What if the glow plugs in the 1.6 are slow glow and the relay is a fast glow? Would that explain it?

jtanguay · « **Reply #3 on:** October 18, 2008, 03:52:54 pm »

that could... but i thought that using a fast glow on slow glow plugs would burn them out quicker... could be wrong though!

Vincent Waldon · « **Reply #4 on:** October 18, 2008, 04:13:21 pm »

Finish the job !! No temperature sensor means the relay thinks it's very cold and will leave the plugs on a long long time.

The "fast" part of "fast plugs" just means that the car is ready to start "faster"... the plugs still stay on longer when it's colder... and without a temp sensor your relay thinks it's very cold.

BlackTieTD · « **Reply #5 on:** October 20, 2008, 10:16:25 am »

i agree, either finish out the install with the temp sensor or just put the glow plugs on a manual switch (in-line fused) until its all hooked up right.